[PATCH v2] serial: pl011: Add Device Tree support to request DMA channels

[Russell King - ARM Linux]

On Thu, Apr 18, 2013 at 09:14:16AM +0100, Lee Jones wrote:
> @@ -269,7 +270,10 @@ static void pl011_dma_probe_initcall(struct uart_amba_port *uap)
>  	dma_cap_zero(mask);
>  	dma_cap_set(DMA_SLAVE, mask);
>  
> -	chan = dma_request_channel(mask, plat->dma_filter, plat->dma_tx_param);
> +	chan = dma_request_slave_channel_compat(mask,
> +				(plat) ? plat->dma_filter : NULL,
> +				(plat) ? plat->dma_tx_param : NULL,
> +				uap->port.dev, "tx");
>  	if (!chan) {
>  		dev_err(uap->port.dev, "no TX DMA channel!\n");
>  		return;

This suffers the same problem with your MMCI patch.  If you're using DT and
don't provide the DMA information, you get errors printed.  That's not on
for an optional driver feature, especially when that feature causes
functional difficulties on various platforms and so is _purposely_ omitted.